1. Field of the Invention
The present invention relates to survival masks for use in hazardous environments for protecting persons against the dangers of smoke and toxic gases, and more particularly, to a simple, lightweight and easily deployable mask designed for use by an individual within a hazardous environment such as a fire in emergency escape situations.
2. Description of Related Art
It is well known that toxic gases, inhaled by individuals, cause many fatalities in fire related emergencies. The loss of life and property resulting from fires in the United States and Canada occurs at twice the rate at which it occurs elsewhere in the developed world. Two-thirds of all fatal fires occur in single or two family homes. In addition to the 5,000 victims who perish annually in these fires, another 300,000 are hospitalized for prolonged medical and surgical care of their burns.
When occupants of a structure on fire are exposed to the fire byproducts, the first hazard encountered is usually smoke containing particulates and toxic gases which cause immediate visual degradation, obscuration, tearing and painful irritation of the eyes as well as the respiratory tract. This may be followed quickly by incapacitation due to pain, severe visual impairment and asphyxia as exposure continues. Fires burning in highly combustible structures tend to develop rapidly and the time available for escape is often limited to a few minutes before conditions become lethal due to the effects of toxic smoke and heat, so that survival depends on rapid egress. Visual obscuration and severe smoke irritation are important during the early stages in that they may reduce visibility and hence, the speed and efficiency of escape. People have been shown to be reluctant to enter smoke filled areas even if such areas are between them and the exit, and it has been found that movement is greatly reduced under these conditions. Once certain synthetic materials within the structure become heavily involved in combustion, the concentration of toxic gases, such as CO and hydrogen cyanide (HCN) increase rapidly throughout the structure causing rapid incapacitation of the occupants. Accordingly, the most significant problems encountered by occupants of a burning structure include the inhalation of toxic gases and the blinding effect of smoke.
Furthermore, fire and smoke related fatalities are frequently encountered during aircraft crashes, wherein the aircraft does not totally disintegrate upon impact. Many, if not all of the passengers, initially survive such low impact crashes only to find themselves engulfed in the resulting fire and smoke.
The National Transportation Safety Board has summarized the sequence of events in a commercial airline crash wherein the aircraft encounters a relatively low impact xe2x80x9cbelly-landingxe2x80x9d as follows. Initially, the aircraft skids along the ground, causing fuel lines in the lower fuselage of the aircraft to be severed resulting in a fine mist spray of jet fuel into the baggage compartment. Typically, one of the wings impacts the ground-rupturing wing mounted fuel tanks resulting in additional spray of jet fuel. The jet fuel and associated vapor is typically ignited by a spark generated by the skidding aircraft resulting in a fireball which envelopes the fuselage. Within 30 to 60 seconds of the initial impact, the aircraft typically comes to a full stop with the fuselage generally level and intact. The flames enveloping the aircraft begin to melt the acrylic polymer windows and starts burning through the fuselage.
During the next minute, that is within approximately 60 to 120 seconds of the initial impact, a portion of the aircraft""s interior is ablaze, and the cabin begins to fill with a dense, black, caustic smoke. The major identifiable gases which result in passenger incapacitation following combustion of the cabin interior materials include carbon monoxide (CO), hydrogen cyanide (HCN), hydrogen fluoride (HFl), hydrogen chloride (HCL), nitrous oxides (NOx), sulfur dioxide (SO2), ammonia (NH3), acrolein (Cxe2x80x94Cxe2x80x94) and other hydro carbon compounds. The smoke and poisonous gases incapacitate the weak and elderly almost immediately and the remaining passengers shortly thereafter. Passengers who are still conscious blindly attempt to crawl toward an exit, which, quite typically, is not visible. Within approximately two minutes from the initial impact the cabin becomes a smoke filled inferno, and all passengers remaining in it are asphyxiated by smoke, poisoned by toxic gases or otherwise incapacitated.
There are indications that a substantial number of passengers in low impact aircraft crashes could be saved. Studies have shown that between 1969 and 1983, over 60% of the fatalities in such crashes were caused by suffocation due to the inhalation of toxic fumes, rather than by impact. Between 1985 and 1991 about sixteen percent (16%) of all United States transport aircraft accidents (thirty two (32) accidents) involved fire and twenty two percent (22%) of all fatalities (144 fatalities) resulted from fire/smoke toxicity. Laboratory analysis of post-mortem blood samples for the time period from 1967 through 1993 indicate that 360 individuals in 134 fatal fire related civil aircraft accidents had carboxyl hemoglobin saturation levels greater than or equal to 20%, with or without blood cyanide high enough to impair performance. A number of safety mask devices are known in the background art for use by persons in fire related emergencies. For example, U.S. Pat. No. 4,231,118, issued to Nakagawa, discloses a head and face-protecting hood. U.S. Pat. No. 4,466,432, issued to Wise, discloses an air-supplying hood which requires an external air supply to provide breathable air to the user. U.S. Pat. No. 4,793,342, issued to Haber et al., discloses an emergency smoke hood and breathing mask having an activated charcoal filter for removing smoke and/or toxic gases. U.S. Pat. No. 5,113,854, issued to Dosch et al., discloses a quick-donning protective hood assembly having a built-in oxygen generator. U.S. Pat. Nos. 5,186,165 and 5,315,987, issued to Swann, each disclose a filtering canister with deployable hood and mouthpiece, wherein the filtering canister includes various layered filtering material including activated carbon granules, a desiccant, a catalyst for the catalyzation of carbon monoxide to carbon dioxide and/or lithium peroxide for conversion of CO2 to O2, and electrostatically charged filters between the layers of filtering medium. U.S. Pat. No. 5,526,804, issued to Ottestad, discloses a complex self-sufficient emergency breathing device. U.S. Pat. No. 5,690,095, issued to Glynn et al., discloses an emergency escape breathing apparatus requiring a source of respirable gas.
The devices of the background art, however, do not disclose a simple, lightweight, easily deployable mask designed for use in modern fires. For example, U.S. Pat. No. 2,665,686 issued to Wood discloses a rather large device which is neither compact or flexible, and thus not well suited for storage within small storage compartments, handbags or carry-on luggage. In addition, it has been found that people, particularly when in distress, are reluctant to completely cover their heads with hooded devices.
Hoods of the prior art are bulky, cumbersome to put on, require up to five minutes to do so, contain huge amounts of dead space (the space occupied by a women""s hair style, for example), are difficult to seal around the neck and contain as part of the apparatus a canister for filtration and an exogenous supply of O2. Hoods are for trained personnel, i.e., flight attendants, firemen, paramedics, rescue personnel, with responsible roles to play in emergency fire situations and long durations of exposure anticipated in carrying out those responsibilities.
Conversely, the mask of the present invention is specifically designed to provide the frightened lay person trapped in these awful environments with something they can use easily and will provide them with clear vision, clean breathable air, scrubbed of irritant smoke particles and toxic gases for a limited period of time.
Accordingly, with the devices of the background art, any toxic smoke which enters the mask, either through a faulty seal or faulty filtering apparatus, will result in irritation of the wearer""s eyes. Many fatalities can be prevented in fire related emergencies if a person""s eyes were protected from exposure to toxic smoke and if filtered breathing air were available so that the person could avoid the harmful effects of toxic smoke while escaping. Therefore, there exists a need for a flexible, compact lightweight mask for providing both respiratory and visual protection in modern fire environments.
A simple, light-weight, easily deployable survival mask designed for use in modern fires. The survival mask of the present invention is made of a simple design, resembling a surgical mask, and is designed to be used by the lay person, with no previous training or experience in emergency situations such as an aircraft fire or a home, hotel, or high rise building fire. The mask substantially covers a wearer""s face and includes a peripheral adhesive seal for preventing contaminants from effecting the wearer""s visual or respiratory systems. The peripheral seal preferably comprises an adhesive band employing the skin adhesive commonly used in surgical masks. The adhesive band provides for closed attachment of the mask to the brow, the temporal area, cheek, over the jaw and down under the chin. The mask is secured firmly to the wearer""s face by adjustable, resilient straps detachably affixed to opposing sides of the mask body such as VELCRO(trademark).
The adhesive band provides for closed attachment of the mask to the brow, the temporal area, cheek, over the jaw and down under the chin. The mask is anchored firmly to the head of the wearer by resilient straps. Thus attached, the mask seals the eyes, nasal passages and mouth from the toxic external environment.
The mask is comprised of an upper, visual portion and a lower, respiratory portion. A further feature of the mask is the provision of an intermediate seal separating the upper, visor portion and the lower, respiratory portions of the mask to form a separate sealed visual compartment and a sealed breathing compartment. The upper portion defines a visual compartment including a substantially transparent section and is separated from the breathing compartment by a soft metal band with an adhesive seal which is shaped to conform to the nasal bridge and orbital rim. The proper orientation of the mask is easily identified by the presence of a highly visible colored outline around the periphery of the mask. Instructions, a photograph, or a drawing can be included with the mask packaging to provide guidance to the user as to which colors correspond to which facial feature. Further instructions can instruct the user how to fracture the vials containing the perfluorocarbon solution, contained in the respiratory portion of the mask, which provides an independent source of oxygen to the user.
The upper visual compartment extends outward from the eyes and protects the eyes and is designed to fit over eyeglasses of any size so that the eyeglasses do not have to be removed to wear the mask.
The upper visual compartment provides protection for the delicate epithelial lining of the cornea and the conjunctiva from the irritant, particulate-laden smoke and accompanying toxic gases such as CO, HCN, etc., in the ambient atmosphere of a fire. Failure to protect the eye tissue from these toxins can result in a profound loss of vision, so necessary to guide successful escape from a fire. The adhesive band molds around and seals the eyeglass temples.
The thermostability of the mask material offers protection from fogging due to the ambient heat of the surrounding area, while the isolation of the visual portion from the respiratory portion of the mask protects fogging due to the water vapor of the user""s exhaled breath. In addition, treatment of the visual portion""s inner surface of clear plastic with de-fogging agents will further reduce fogging and result in clearer vision.
The lower portion of the mask defines a breathing compartment. The mask is impregnated with a particulate filter such as HOPCALITE(copyright) or MOLECULITE(copyright) granules. MOLECULITE(copyright) is an Oxygen catalyst comprised of a mixture of Copper Oxide and Manganese Oxide. The particulate filter provides for the removal of atmospheric dust thereby protecting the wearer""s respiratory system from exposure to airborne particles. Preferably, MOLECULITE(copyright) particles of nanoparticle size (10xe2x88x929 m) in diameter are used. The MOLECULITE(copyright) functions to reduce and absorb the levels of various toxic gases such as CO, CO2, HCN, HCl, H2S, SO2 and olefins (hydrocarbon fragments from the burning of plastic).
Also within the respiratory portion of the mask are one or more frangible vials, each containing a source of molecular oxygen for breathing, dissolved as solute in a supersaturated solution of perfluorocarbon (PFC) liquid. The perfluorocarbon-oxygen liquid is initially contained in thin walled glass ampules embedded within flanking pouches surrounding a respiratory cup. The respiratory cup is generally comprised of melt blown electret microfibers, similar to that disclosed in U.S. Pat. No. 4,215,682 issued to Kubik et al. and U.S. Pat. No. 3,971,373 issued to Braun, each incorporated herein by reference.
As soon as the mask is opened from its packaging, the glass ampules become ruptured, and the breathing compartment is flooded with the perfluorocarbon liquid which is absorbed by the particulate filter. The oxygen is released into the body of the mask by physical diffusion immediately upon rupture of the vials. The particulate filter, MOLECULITE(copyright) and perfluorocarbon, function to filter out particulates, absorb toxic chemicals and provide a source of oxygen to the wearer. The mask is easily applied in a matter of 30 to 60 seconds. The major and unique function then of the PFC is as a carrier of oxygen readily available for breathing as soon as the ampules are ruptured and the PFC enters the respiratory cup.
After release from its carrier vials, the liquid PFC releases its dissolved oxygen and assumes its second function, that of a non-toxic, non-irritant, biologically inert, well tolerated wetting agent to help trap particulate material present in the dense acrid smoke of a home, hotel or aircraft cabin, in the respiratory portion of the survival mask.
The mask is capable of being folded into a very compact storage configuration, such as a sterile plastic and fire resistant Peel Pack(trademark) container, and will easily fit into a women""s purse, a man""s jacket, a briefcase or the storage compartment behind aircraft passenger seats.
Upon removal from its container, the mask is easily applied by utilizing the color-coded flanges corresponding to the parts of the face to which each part is applied. In fact, the color-coding scheme is critical since once the mask is folded and stored it must be unfolded and properly configured on the user""s face. The color-coding scheme therefore allows the layperson to properly place the mask on his or her face, normally a trivial maneuver, yet which becomes alarmingly more difficult under the duress of hazardous conditions. Because the prior art protective hoods are rigid and inflexible, and therefore cannot be folded for storage purposes, there is no need for a color scheme of the type utilized by the present invention.
The flexible design of the mask fits the size and conformation of differing facial anatomy and adheres to the skin surface of the face, brow and chin of the wearer by means of moldable flanges of elastomeric material impregnated with a non-stringy hydrophilic adhesive gel. The visual and respiratory compartments are separated from each other by that same impregnated elastomeric material contained in a soft aluminum band moldable to the contour of the nasal bridge to prevent leakage between the two compartments. Finally, the mask will be firmly secured to the head by any typical securing means, preferably two soft VELCRO(trademark) straps adapted to fit any head size.
Accordingly, it is an object of the present invention to provide a simple, lightweight, easily useable survival mask designed for use by any individual within a hazardous environment such as a fire in emergency escape situations.
A further object of the present invention is to provide a survival mask having an intermediate seal separating upper and lower portions of the mask to form a separate sealed visual compartment and a separate sealed breathing compartment.
Yet another object of the present invention is to provide a survival mask with an easy-to-use color-coded scheme to enable the user to properly configure the mask on his or her face.
Still another object of the present invention is to provide a survival mask wherein the wearer""s respiratory system is protected by a MOLECULITE(copyright)-impregnated particulate filter saturated with oxygen-loaded perfluorocarbon.
Another object of the present invention is to provide a small, packagable, portable and easily accessible survival mask that can easily stored, transferred, removed and deployed when needed.
In accordance with these and other objects which will become apparent hereinafter, the instant invention will now be described with particular reference to the accompanying drawings.